The present disclosure relates generally to LED light lamps, more particularly to LED light lamps as replacements for incandescent bulbs or compact fluorescent light bulbs.
Incandescent light bulbs are commonly used in many environments, such as households, commercial buildings, and advertisement lighting, and in many types of fixtures, such as desk lamps and overhead fixtures. Incandescent light bulbs can each have a threaded electrical connector for use in Edison-type fixtures, though incandescent bulbs can include other types of electrical connectors such as a bayonet connector or pin connector. Incandescent light bulbs generally consume large amounts of energy and have short life-spans. Many countries have begun phasing out or plan to phase out the use of incandescent light bulbs entirely.
Compact fluorescent light bulbs (CFLs) have been gaining popularity as replacements for incandescent light bulbs. CFLs are typically much more energy efficient than incandescent light bulbs, and CFLs typically have much longer life spans than incandescent light bulbs. However, CFLs contain mercury, a toxic chemical, which makes disposal of CFLs difficult. Additionally, CFLs require a momentary startup period before producing light, and many consumers do not find CFLs capable of producing light of similar quality to incandescent bulbs. Further, CFLs are often larger than incandescent lights of similar luminosity.
LED light lamps have been developed as an alternative to both incandescent light bulbs and CFLs. These LED light lamps each typically include a base, a group of LEDs attached to the base, and a bulb. The base normally has a structure of fins as a heat sink, and an electrical connector, such as an Edison screw base, at one end. The bulb often has a semi-circular shape with its widest portion attached to the base such that the bulb protects the LEDs.
The structure of fins complicates the design of an LED light lamp, though. The structure of fins could shadow the proximity of the base from the light emitted from the LEDs, making the luminous distribution of the LED light lamp very different from that of an incandescent light bulb. The other solution of improving heat dissipation is using metal column extending from the base toward the center of the bulb. LEDs are mounted on the lateral surface of the metal column, which serves both as a heat path between the LEDs and the base, as well as a way to elevate the LEDs for an omnidirectional light pattern. This metal column is costly, however, in view of component cost and assembling process.